Apparatus for cleaning wells



June 26, 1934. Q `MACK APPARATUS FOR CLEANING WELLS Original Filed Deo. 2l, 1929 MMM Patented nFunc 26, i934 AT v Application December 2l, 1929, Serial No. 115.6911

i Renewed April 6, 1934i 3 Claims.

rIhis invention relates to novel apparatus and method for cleaning wells.

One object of the invention is to provide apparatus of the character described whereby an oil well or other well which has become clogged up may be cleansed and freed from the clogging material and the capacity of the well thereby maintained or increased.

Another object of the invention resides in the lo provision of a novel process which may be carried out by the use of said apparatus.

In the production of oil, a screen is usually set in the well opposite the oil bearing strata and it oftens happens that a clogging material such as l5 parain collects on the screen and clogs the same so as to reduce or destroy its screening capacity and the fluid is thus partially or entirely excluded and the production of oil decreased or stopped. This clogging material also may collect 2o on the walls of the bore so as to seal or partially seal said walls and retard or stop the flow of oil to and into the screen. It is the principal object of this invention to practice a novel method and employing a novel apparatus for carrying said method into eiect, whereby the clogging material referred to may be disintegrated or dissolved and thus removed from the screen or the walls of the bore and pumped out of the well and the uid sought thus permitted to freely ilow into the screen.

With the above and other objects in view this invention has particular relation to certain novel features of construction, operation and arrangement of parts of the apparatus, and to a' novel method, examples of which are described in this specication and illustrated in the accompanying drawing, wherein:

Figure 1 shows a vertical sectional view of the apparatus shown in position for forcing a cleansing and disintegrating medium from within the screen out through said screen.

Figure 2 shows a fragmentary vertical sectional view thereof shown in position for forcing said cleansing medium downwardly through the apparatus and up about the screen on the outer side thereof.

Figure 3 shows a cross sectional view taken on the line 3--3 of Figure 1.

Figure 4 shows a cross sectional view taken on the line 4-4 of Figure 1;

Figure 5 shows a cross sectional View taken on the line 5--5 of Figure 2, and

Figure 6` shows a vertical sectional View of pump means for removing the disintegrated, or dis` solved clogging material from the well.

(Cl. ll66-2@) Referring now more particularly to the drawing wherein like numerals of reference designate similar parts in each of the iigures, the numeral l. designates the well bore in which is located any conventional type of well screen 2 which is usually attached to the lower end of the tubing 3 extending to the ground surface.

In the lower end of the screen there is secured a suitable valve seat 4 which is controlled by the downwardly opening back pressure valve 5 hor-u mally heldclosed by the pressure spring 6.

When the screen or the surrounding walls oi the bore become clogged, a' paramn solvent is poured down into the well in a sufficient quantity to dissolve the oiending clogging material.

In Figures 1 and 2 there is shown a type of apparatus by means of which this solvent may be advantageously applied so as to effectively dissolve or disintegrate the clogging material. This apparatus will now be describedz The numeral 7 designates a string of pipe which extends up to the ground surface and whose lower end may be reduced as at 8 and provided with perforations as 9. The lower end of the reduced portion 8 has a transverse web l0 provided with the outlet ports 1l an depending from this web there is a stern 12 whose lower end has a` disc Avalve 13 attached thereto. Fitted over the re'- duced portion 8 there is a sleeve valve 14 whose upper end has the perforations 15. The upper end of the valve 14 abuts the external shoulder 16 on the string 7 and threaded into the lower end of said sleeve valve there is the disc 17 having the perforations 18 therethrough. The `Vdisc valve 13 is provided with perforations 19 adapted to be brought into and out of registration with the perforations 18.

The reduced portion 8 has an arcuate slot 20 out therethrough and the valve 14. has a pin 21 screwed therein and projecting inwardly into said slot, said pin forming a stop. When the. string of pipe is turned in one direction until stopped by the pin 21 the perforations 9, 15 will be brought into alignment and the perforations '18, 19vwil1 be brought out of alignment. The solvent, above referred to, may then be forced by fluid pressure out through said aligned perforations and out through thescreen and will thus effectively cleanse said screen as well as the walls of the bore and dissolve the offending material .collected therein. While in this position the string of pipe may be elevated and lowered and the screen thoroughly cleansed from end to end. The string of pipe 7 may be turned in the other direction until stoppedby the pin 21 and this will close the ports 9, l5 and align and open the ports 19, 18 and the solvent may then be forced on down through said aligned ports and on down through the valve seat 4 lifting the valve 5 and pass up around the outer side of the screen for the purpose above stated. For the purpose of holding the valve 14 against turning the lower end thereof is provided with suitable teeth 22 which will engage the valve A. and hold the valve 14 against turning movements when the string of pipe '7 is turned.

After the paraffin or other offending material has been so dissolved it is then pumped out of the well. In order to accomplish this, the apparatus for applying the solvent shown in Figures 1 and 2 is withdrawn from the well and a pump mechanism is lowered into the well. This pumping mechanism comprises a long cylinder 23 which is attached to and lowered into the well by the tubing 24 which extends to the top of the well. Attached to the lower end of the cylinder 23 there is an inverted conical shaped guide 25 whose lower end has the inlet opening 26, controlled by the upwardly opening valve 27. Fitted in the cylinder 23 there is a plunger 28 having the fluid passageways 29 upwardly therethrough, whose upper ends are controlled by the valves 30 which are confined by the cages 3l carried by said plunger. This plunger is attached to the lower end of the sucker rod 31 which extends to the ground surface and which is operated by a suitable walking beam or other similar apparatus. The sucker rod works through a spider 32 at the top of the cylinder 23 and this spider has the openings 33 therethrough controlled by the suitable upwardly opening flap valves 34.

When the pump is located in the well upon downward movement of the plunger 28 the fluid in the well will pass upwardly above said plungers and upon upward movement of the plunger, the fluid in the cylinder 23 will be forced on up through the tubing 24 and will eventually be discharged out of said tubing at the ground surface and the dissolved clogging material thus be readily disposed of. By reason of the length of the cylinder 23 the plunger vwill have a long travel and upon its upward stroke will create a strong suction through the screen and on the walls of the bore and will effectively cleanse the same.

The drawing and description disclose what is now considered to be a preferred form of the apparatus and a preferred method of cleansing a clogged well by way of illustration only while the broad principle of the invention will be defined by the appended claims.

What I claim is:

1. A device of the character described comprising a tube whose lower end has a perforated section and a lower end-opening, a stem carried by the lower end of said tube, a sleeve valve arranged vto cooperate with the perforated lower end of said tube, said valve having perforations and being provided with a lower end-opening, means on the stem arranged to control the lower end-opening of said valve, means for holding the valve stationary as said tube is turned whereby the perforations of said tube may be brought into and out of registration with the perforations of said valve.

2. A device of the character described cornprising a sleeve valve having a lower end-outlet and having a perforated section, a tube having a perforated section telescopically arranged with respect to said valve, said tube being turnable to carry the perforations thereof into and out of registration, with the valve perforations, means arranged to be operated by said tube and effective to close said lower end-opening when said perforations are in registration and to open said lower end-opening when said perforations are out of registration.

3.A device of the character 'described com- 110 prising a sleeve valve having a lower end-outlet and having a perforated section, a tube having a perforated section telescopically arranged with respect to said valve, said tube being turnable to carry the perforations thereof into and out of registration with the valve perforations, means arranged to be operated by said tube and effective to 'close said lower end-opening when said perforations are in registration and to open said lower'end-opening when said perforations are 120 out of registration, and means for limiting the turning movement of the tube relative to said valve.

JAMES O. MACK. 

